[CA] [CA11] e7 problems - Should I repair or replace? Axiom? New e7?

[Pamlico]

I purchased a Raymarine e7 in December 2011. It was replaced under warranty in June 2012 and again in May 2014, but it is still not working properly. It is a 43' sailboat.

On a clear sunny day everything works great and is just what we need.

On a tough recent passage we were reminded the touch screen is 100% non responsive in rain or rough sea conditions where salt spray hits the screen. The scroll wheel also is, and has always been, non functional. It doesn't scroll, it creates havoc and zooms unpredictably in and out to random areas. When the touch screen is working we can use the + and - signs to successfully scroll in and out, but when the moisture is high we lose that option. We are flying blind in rough weather, and can't use our MFD even to look at radar or our AIS positions.

I could send it in for repair, but will it help? We have an exposed helm, and the MFD is in a NavPod, but the screen is going to get wet in rough seas.

What should I do? Should I replace with an Axiom? Does the touchscreen on the Axiom work better? Should I buy a new e7 - and if so, is there a difference in the new units? Should I send this one in for repair or am I throwing "good money after bad?"

Everything I have is Raymarine, so I am looking for a good Raymarine solution, but the e7 we have is not really working.